Process of producing uniformity of quality in molten metal.



No, 7364131. PATENTED AUG. 11, 1903).

v R. G. G. MOLDENKE. PROCESS OF PRODUGINGUNIPORMITY OF QUALITY IN MOLTENMETAL.

APPLICATION FILED JULY 10, 1900.

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I DENKE, a citizen of the United States, resid To a, whom it mayconcern:

UNITED STATES Patented August 11, 1903.

ATENT 'FFICE.

PROCESS OF PRODUCING UN IFORMITY F QUALITYIN MOLTEN METAL.

SPECIFICATION forming part of Letters IPatent No. 736,131, dated August11, 190 3.

Application filed July 10,1900. $erial No. 23,0 69. (No specimens.)

- Be it known that I, RICHARD G. G. MOL- ing at Pittsburg, in the countyof 'Allegheny,

State of Pennsylvania, have invented or 'dis covered a certain new anduseful Improve- 1 Hcretofore,so far as I am aware, it has been uniformquality. To illustrate: Suppose we drawfrom a heat of malleable ironwith aand cast the metal so drawn in a casting of V Wefind' that thement in Processes of Producing Uniformity of Quality inMolten Metal, ofwhich improvement the following is a description.

My invention relates to processes for producing uniformity of q'ualityinmolten metal, cast-steel, and malleable-iron castings.

impossible to attain uniformity of quality in metal in any given heat ormelt, as when tapped or poured from or near the bottom of the furnace,as at present practiced, metal widely difier ing in quality is withdrawnat each pour or tapping, making it impossible to utilize the entire meltin castings ofrequired composition of .75 silicon from or near thebottom, where the temperature of the metal is lower than that at ahigher level or plane,

two-inch-square section. metal is of the quality known as a 5 gray iron.

If, however, at the same instant we tap the furnace slightly below thepla'ne'of the molten metal, where the temperature of the metal is.considerably higher than at the bottom, and

cast the metal drawn therefrom into a cast ing of the same size as inthe preceding instance mentioned, we find that the metal is of a qualityknown as a white iron. In the metal drawn from the bottom we also findthat the carbon oft-he composition has separated in the form ofgraphite, whereas in the metal drawn from the top the carbonremainscombined. Under the present method of melting and pouring the metal wethus unavoidably obtain metal of varying and different quality.

The object of my invention is to obviate this difliculty and produceuniformity of quality in molten metal, cast-steel, and malleableironcastings, and to this end my invention consists in the following methodof treating the metal and pouring the same.

Figure l is a front elevation of a furnace which can be used inconnection with my process, and Fig. 2 an end view of the furnace.

I charge a furnace of any usual construction in the usual manner toproduce when melted metal of any required composition. After the metalat a higher level or plane has been brought to the proper temperature,and by test, the required quality I tap the furnace at a point below theplane of the molten metal sufficient to withdraw metal of the requiredquality. After the metal has been withdrawn to such point the pouring isdiscontinued and the heating continued until'the metal then at the topof the furnace has attained the temperature and quality of thatpreviously with drawn. The furnace is then tapped a distance below thelevel or plane of the metal corresponding to thefirst and the metalwithdrawn, as in the previous instance, and these A steps continueduntilthe entire heat has been the top of the furnace to a desirabletemperature and quality, then tapping the same a short distance belowthe plane of the metal and pouring therefrom until the metal varies intemperature and quality from that required, then suspending the pouringa short time until the metal at the top, which is ata lower level thanbefore, again attains the temperature and quality previously secured,then tapping the metal below the plane thereof, a short distance belowthe point of the previous tapping, and pouring therefrom, and thesesteps continued until the heat or molten metal has been withdrawn.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

RICHARD G. G. MOLDENKE.

In presence of CLARENCE A. WILLIAMS, JOHN H. HONEY.

